I doubt this will be implemented in a near future.
I want to suggest a special feature (could have been mentioned before) for Theocracies.
They should have an option to declare the main religion of the realm. Unlike other government systems, theocracies should only allow one religion. Knights of a theocracy should have an option to 'purge' heretics or heathens to stop other religion from spreading.
I think it would be best for all systems to have the option of having a state religion, with different effects on that religion and the realm depending on the realm type.
